


Creature feature

by Yellowbirdbluetoo



Category: The Last Kids on Earth (Cartoon)
Genre: Basically Jack is feral, M/M, Shoutout to the tlkoe discord peeps for some of the concepts, but like in a cute feral kitten way
Language: English
Status: In-Progress
Published: 2020-11-27
Updated: 2021-02-15
Packaged: 2021-03-08 20:20:51
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 4,166
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27472666
Author URL: https://archiveofourown.org/users/Yellowbirdbluetoo/pseuds/Yellowbirdbluetoo
Summary: It’s not too weird to suddenly have sudden boughts of insomnia right?Okay, maybe the urge to start hunting is a bit much?
Comments: 13
Kudos: 36





	1. Chap.1

**Author's Note:**

> Uhh yeah, basically Monster! Jack au lives in my head rent free and I had to write this to get it out. I think this is 3rd fic in progress for this fandom, so feel free to check out my other stuff. And without further ado, here you go

**Summary for the Chapter:**

> Something strange is a happening here

**Notes for the Chapter:**

> I said I’d post this link in the discord like 3 days ago sorry
> 
> Also idk remember if the treehouse has a kitchen and at this point I’m too afraid to ask so let’s say the kitchen is a dinky microwave and mini fridge and some cabinets

It’s been nearly a week since they’ve closed the portal, and ended the whole Thrull and Rezzoch apocalypse thing. Things have been relatively calm ever since-well as calm as it can be between with a bunch of teenagers and monsters coexisting- but they’re repairing things as well as they can.

Everything starts one night, when he’s trying, desperately, to fall asleep. Usually it’s easy for him to drift off to dream land after working all day on fixing up the treehouse and adding more defenses to their little area of town, leaves them all exhausted by the end of the day. 

But tonight, he’s got this itch in his bones. To move and to get up and go do... something. He isn’t sure what.

He sits up in his bed- a pile of old clothes and blankets- he’s fought against the others multiple times because he doesn’t want the hassle of getting a mattress- and runs a hand through his messy and unruly bed head.

The old nightlight in his room that he’d swiped from a house during a patrol once, flickers as he walks past it, quietly sneaking out of his room and to the kitchen.

None of the snacks they have really catch his eye, not even his favorite flavor of chips that’s super hard to find. His eyes linger on some tool, probably from Quinn’s pile of supplies or Dirks gardening stuff, left on the table of their makeshift kitchen area. 

His teeth throb with a sudden dull ache and the thought comes to his mind seemingly out nowhere, ‘chew on it’

He shakes his head to clear the thought away and scowls at himself. Where the hell did that come from. He is not some dog, he’s not about to go chewing on piece of metal, that’s ridiculous. He glares at the wrench, snatching a bag of chips and storming quietly back to his room. 

The chips taste stale on his tongue.

He lets himself get lost in his imagination to pass the time, and his eyelids don’t begin to drop until the rising sun starts peaking through his window. He turns away from it, pulling an old shirt over his eyes and finally falling asleep.

-/-

Waking up to June shouting at him to get his ass up isn’t as funny as it usually. Normally he’s had a good nights sleep. Now he reckons he’s only had about three hours or so.

Quint calls for him next, and he sits up blearily, eyes squinting at the harsh sunlight as he stretches. Three hours is better than none he supposes. He’ll just have to take it slow today. 

The others are already waiting for him when he stumbles into the kitchen. He rifles through through their food supply, even though he’s not feeling particularly hungry for anything there, grabs something at random and sits next to Dirk on the couch so he can listen to Quint tell them what they need to get done today.

“June, you already know what you’re doing, Dirk, can you check the outer perimeter of town? I want to be sure that nothings out of the ordinary”.

Dirk gives a nod, and June looks up from sharpening her spear to say something, but her eyes land on Jack and widen in surprise. “Woah dude, did you get any sleep at all last night?”.

Dirk snickers. “With those bags you’ve got, I’m guessing all you did was shop?”.

Jack huffs, shoving another-he looks down... he’d grabbed a bag of croutons... whatever he shoved another crouton into his mouth. “I couldn’t really sleep last night. Don’t worry about it I’ll be fine, honest”.

Quint levels him with a worried look but continues anyways.

They all start heading out, but before Jack can get on Rover- he’s supposed to be looking for supplies again- Quint stops him. The others are well out of hearing range when Quint starts speaking. “Are you sure your okay?”.

Jack blinks, momentarily confused. “Uh yeah? I’m fine. One bad night of sleep isn’t gonna kill me”. 

Quint looks doubtful. “Your version of fine is other people’s version of 'I seriously need help’. I’m just..”. 

“Worried?”. Jack nudges Quint playfully with his shoulder. “Don’t worry. If it makes you feel any better, I’ll finish as fast as I can and get back here to take a nap”. It doesn’t sound half bad to himself, he’d take one right then and there if he could. But staying behind to sleep would just make the others worry more.

Quint nods. “Okay. Just, be careful out there friend”. He gives Rover a pat on the head. “Watch after him boy?”.

Rover wags his tail, not at all in understanding, but Quint seems satisfied enough so he waves Jack off.

Patrolling goes as normal as it ever can. He marks down zombie routes, checks to see if anything’s out of the ordinary. 

He parks Rover by the side of the woods with a yawn, and tosses him a treat. “I’ll be back in a sec buddy”. He slides his pack off of the dog monster, who barks happily in reply, and starts his trek into the woods. 

He liked how calm the woods are compared to rest of town. It’s a little unsettling to think of that just two weeks ago, they’d battled and defeated Rezzoch here. Part of him wanted to completely avoid the area where the whole thing had occurred, but he was on patrol and that meant he had to check and make sure they area was the same as when they’d left it. 

He carefully stepped over some tree roots and gripped his bat tighter as he scanned around the area that was still somewhat thoroughly wrecked. Quint has theorized that Rezzoch’s leftover magic had permanently altered the area, and that it would probably stay a charred and dirty mess. 

Jack’s thoughts were interrupted by a sound coming from behind him and he whirled around to face a bush that was rustling loudly. He narrowed his eyes and readied his bat to attack.

The rustling halted and after a moment, a white rabbit hopped out. 

Jack let out a sigh of relief, lowering his bat as the rabbit twitched it’s nose at him, uninterested in his presence.

He let out a light chuckle which startled the thing enough to send it hoping away into the woods. 

Quick as lighting in his mind, the thought appeared. ‘Chase it’. 

He stared after the rabbit for a moment, before taking a step towards it, then another, and another until he broke out into a sprint after it, chasing it deeper into the woods. 

The rabbit raced ahead of him into a dead end, pressing itself against the bunch of rocks that it was corned between. 

Jack stood above the animal, panting from having to run so far, and paused. What the hell was he doing? He let his bat fall to the ground and shakily stepped away from the rabbit, who raced off with no hesitation and this time Jack didn’t follow. 

He took a moment to catch his breath, picked up his bat, and began making his way back to Rover. 

-/-

He was the first one back, and was glad for it. No way was in the right headspace to come up with a good enough lie to fool the others on his gloomy mood. 

He dropped Rover off at the bottom of the treehouse, giving him a weak pat on the head before moving to climb up the treehouse ladder and getting to his room. 

He kicked off his shoes and leaned his bat against the wall, then collapsed onto his bed, closing his eyes, and hoping that sleep would overtake him easier than it had last night. 

-/-

He wakes up to a dark room and a quiet treehouse. He sits up blearily blinking sleep from his eyes and gets up to check his watch that he’d tossed across the room the other day. 

“Oh shit, it’s two in the morning? Why didn’t anyone wake me up?”. 

His stomach growls, and he decides a midnight snack might at least soothe his mood. ‘The nap did wonders’ he thinks as he stretches, and creeps out of his room and down the kitchen, looking around for something to eat. 

His eyes land on the same tool that he’d seen last night and his teeth ache once again and he hesitates. People don’t chew on tools, right? People chew on their lips, or fingernails, or pencils. Who’s to say no ones ever chewed on a tool? 

He glares at it, but sighs and relents. He’s just gonna try it out’ he vows to himself. He grabs it and lifts it to his mouth. 

He tries to bite it like a corndog, and he expects a toothache or at least for it to scrape his tongue but all it does it bend under the strength of his teeth. 

His eyes widen as the ache in his teeth fades for a moment. He goes for it again, less hesitant this time, and the ache subsides completely for a full few seconds. 

He pushes away his inhibitions and decides to commit. He feels like, well like Rover when he finds a stray pipe to chew on. Which is to say satisfied. 

He’s so lost in the joy of his teeth not aching anymore that he misses the sound of someone creeping up on him until it’s too late. 

“Jack?”. 

He startles, letting out a yelp, and whirling around to face Quint who’s squinting at him in the darkness. 

“Quint! You scared the crap out me! What’re you doing in here so late?”. 

Quint raises an eyebrow at him. “I could ask you the same thing? We got back and you seemed tired so we decided to let you sleep. Are you feeling better?”. 

Jack waved him off. “Yeah yeah, way better. I told you not to worry I just needed a nap”. 

Quint nods tightening his robe around himself. “Okay, good. Uh, may I ask why you’re in the kitchen in the dark?”. 

Jack tilts his head in confusion. “It’s not dark in here? It’s not as bright as it is during the day, but not so bad we can’t see”. 

Quint shakes his head. “Dude it’s like pitch black in here. That’s why I accidentally snuck up on you, I couldn’t find the lights”. 

Jack huffs out a laugh. “It’s not dark in here. Check this, how many fingers am I holding up?”. 

Quint squints at him again. “It’s pitched black friend. Are you saying you can see in the dark?”. 

Jack waves his three held up fingers in Quint’s face with a roll of his eyes, but his friend doesn’t even blink at them. 

“Wait, okay, let me get the lights”. 

He moves to flick the light switch and they flash on so bright that he drops the tool from his hands and has to cover his eyes. 

“Are you alright there?”. Quint says with concern. He leads Jack to a chair so he can sit and turns to pick up the tool he dropped. He raises an eyebrow, holding it up between pinched fingers. “Uh, why is this wet?”. He squints at the tool for a second more. “And bent?”. 

He tilts his head, coming to a realization. “We’re you chewing on my socket wrench?”. 

Jack peeks through his fingers sheepishly, hands still slightly covering his eyes from the harshness of the kitchen light. “Maybe?”. 

But Quint’s mind has quickly let the thoughts of the tool exit. “Your teeth!”. 

Jack tilted his head. “What? I mean, I haven’t really been brushing everyday, but they can’t be that bad-“. 

“No! I mean”. Quint lets the wrench drop the floor as he darts out of the room and digs around the clutter of the living room. He returns with a mirror. 

“Look!”. He thrust the mirror into Jack’s hands, who accepts it reluctantly. His eyes widen in surprise as he looks at his reflection. “Holy shit!”. 

His teeth, which were normal the last time he’d seen them, had sharpened immensely. He ran his tongue over them, testing their sharpness and wincing as one particularly sharp fang pricked his tongue. It was then he looked up and noticed his eyes. 

“Quint”. He said, voice strained. “Turn the lights off for a second”. 

Quint look confused but obliged, hitting the light switch and watching the room plunge into darkness, except for one spot that held a dull glow of light. 

“Quint”. Jack spoke after swallowing roughly. “My eyes are glowing! Why are my eyes glowing?!”. He asked beginning to panic. 

Quint leaned in closer, eyes wide in fascination. “Incredible. This is quite unprecedented. Let me get my charts-“. 

“Quint!”. Jack said on the verge of completely panicking. “I need best friend Quint, not scientist quint please!”. 

Quint blinked and shook his head. “Right sorry. Tests can wait till later. How are you feeling”. He placed a hand on Jack’s shoulder for reassurance, sending heat rushing to Jack’s face. “Well right now, I’m freaking out!”. He whisper-yelled, fighting to keep his voice down as to not alert June or Dirk. 

“Then let’s go outside. Get some fresh air?”.


	2. Chap.2

**Summary for the Chapter:**

> Reassurances and Jack essentially gets a check up

**Notes for the Chapter:**

> Hey hey hey, let me know how u like thisssss by commenting below! Comments keep me going!
> 
> Also I’m completely bs-ing this science

“So, have there been any signs or is this completely out of the blue?”.

They‘re leaning against the base of the treehouse, looking up at the moon, sitting as close as possible to stay warm in the chilly night air.

Jack huffed something similar to a laugh. “I think you all would’ve noticed if I was turning into a werewolf or something. Don’t you think I would’ve said something?”.

Quint turned a skeptical look on his friend. “Absolutely not. And I don’t think this is a case of werewolf-ism. Your not having any reaction to the moon, and I’m not seeing any ears and tails. Not to mention, werewolves eyes don’t glow in the dark”.

“Not to mention, werewolves aren’t real. And something is happening to me”. He reached a hand up without thinking to poke one of his teeth-that were now sharp enough to call fangs. 

“Hmm. Are you sure you don’t wanna tell the others?”.

“Not yet! Maybe this isn’t permanent? I don’t wanna get everyone worried over nothing!”.

Quint raises an eyebrow but doesn’t address his friends obvious denial.

“I could run some tests?”.

At this Jack is the one to raise an eyebrow. Quint levels him with a pleading look and he relents. “Fine fine. I’ll let you go all science on me. Can we wait till tomorrow though? When the others are out?”.

“Absolutely”. Quint grabs Jack’s hand with his own. “I’m sure everything will be fine”.

For the first time in a while, Jack sleeps in Quints room for the night. 

-/-

“Okay, so I have some prewritten notes on what we already know”. 

It’s noon the next day, long after Dirk and June have left off to do their tasks for the day and the latest Quint would let Jack sleep in. They’re in Quint’s makeshift lab, with Quint in his lab coat and his clipboard. 

Jack yawns from where he’s sitting criss-cross applesauce on the couch, still in his pajamas, mindlessly chewing on the same wrench from yesterday. He sighs, resigned to his fate. “Okay, what’d ya got for me doc?”.

“So far, we have evidence that you might possibly be nocturnal”.

“Umm”. Jack smiles sheepishly. “Define nocturnal please?”.

“Something that sleeps during the day, and is active at night. Like bats. Most nocturnal animals have an ultraviolet effect to their eyes, which you exhibited last night, as well as your new change in sleep schedule”.

Jack yawned again as if to prove his point, and took a particularly hard bite of the wrench in his mouth, wincing as part of it snapped off and grimacing as he had to pull out the broken piece. “Sorry about your wrench. Any diagnosis on the whole ‘chewing on stuff’ thing?”.

Quint waved him off. “Don’t worry about it”. He flips a page on his clipboard, and winced slightly. “I don’t know if you’ll appreciate the comparison, but your chewing is very symptomatic of when a puppy is teething”. 

Jack huffs at that, glaring down at the tool in his hand momentarily before rolling his eyes and settling back into the couch. “I don’t appreciate the comparison, but it sounds accurate enough”.

“Has anything else strange occurred?”. Quint questions.

Jack’s eye’s dart to the floor. “I uh, didn’t mention earlier but yeah... something else happened”.

Quint pauses in scanning his notes at Jacks tone. “What happened?”. Concern dripping into his voice as he sat down next to his friend on the couch. 

“I... this is gonna sound so stupid”. He buried his face in his hands, letting out a nervous laugh as he stuck the broken screwdriver in his mouth again for some semblance of calm. “I uh, chased a rabbit in the woods the other day”. He let out a groan of embarrassment as he recalled the event, relaxing only slightly when Quint placed a calming hand on his. 

“I don’t know what I was gonna do when I caught it? It was so weird, I don’t know what was wrong with me. I snapped out of it as soon as I cornered it but like, what if I hadn’t? Would I have...”. He pauses to take in a breath, and his voice cracks when he speaks again. “Would I have killed it?”.

“No!”. Quint is quick to put his hands on Jacks shoulders to ground him before he can spiral. “You wouldn’t do that. And you know how I know that?”.

Jack doesn’t meet his eyes. “How?”. “Because your my best friend and I know who you are”. He pulls Jack into a hug. “Your kind and brave, and your a good person. Your not some wild animal”. He pulls back when he feels Jack relax. “If anything, you’re like an adorable puppy?”. His attempt at joke gets a laugh from Jack which is everything it was meant to do.

“Think we’re gonna have to puppy-proof the treehouse?”. Jack jokes back and Quint chuckles. “Only if you start chewing the furniture”.

Jack playfully shoved, sending Quint onto the floor and they laugh so hard that they Jack ends up on the floor beside him.

**Notes for the Chapter:**

> Shortish chapter but I wanted to have a nice moment with the boys idk if this is gonna be quack but hey :3 who knows anything these days amirite?
> 
> Next chapter: June gets suspicious and Jack seeks monster help


	3. Chap.3

**Summary for the Chapter:**

> Time to seek magical help I guess

“So...what is it?”.

Quint looks exceptionally proud of the small necklace dangling from his hands(Jack recognizes it as the look whenever he’s successfully cooked up a new invention). 

“Essentially, it’s a super durable chewing necklace”. He hands it over to Jack. “And it should be have enough dexterity to withstand your new teeth”,

Jack takes it, looking it over curiously, taking an experimental bite and his eyes lighting up. “Oh my god, dude! This is great! Thanks!”.

Quint shrugs, a proud grin on his face. “It’s what I do”.

Jack smiles, tying it around his neck. “I’m gonna go talk to Bardel. He’s all...”. He pauses, to wiggle his fingers. “Magical”. 

“Sounds good. If you need me I’m just going over town defenses. Let me know if you find anything out”.

“Totally”. He nods. “And remember until we figure something out we aren’t telling anyone”.

“Not telling anyone what?”.

Both boys jump turning to see the other two members of their group entering the treehouse and share a quick glance. “Tell you about...”. Quint trails off.

“Tell you about the thing! That’s a secret! It’s a secret thing! But not like a bad thing! Like, a good secret thing! Don’t worry about it! Not that you should be worrying it’s just-“.

Quint covers his mouth, wincing. “Please stop”.

It’s a moment of awkward silence and Jack laughs awkwardly clearing the air, and moving to leave. “Well I’ll see you guys later bye!”. And slides out of the room leaving behind two bemused people with someone who was a terrible liar.

Smart, as always.

-/-

Bardel, as per usual, is off on his own. Jack has to ask several other monsters where the magical recluse is before he learns that the monster had taken to the town to go inherit more knowledge in the human world 

He saddles up on Rover, chewing necklace in between his teeth as they take off towards downtown.

Jack gets distracted only twice. Once to root through the remains of an old cornershop and the second time to let Rover walk ahead of him, as the large dog enjoyed getting to freeroam around the town. 

“I heard you were seeking my presence”.

He’s throwing an old stop sign as a frisbee for Rover to fetch when the voice startles him enough to make him trip over his own feet and fall on his butt, looking above him to find Bardel levitating slightly above the street.

“Bardel! Just the man, er monster, I was looking for!” 

The monster in question simply raises an eyebrow at the human below him, then rolls his eyes (an expression Jack is pretty sure he learned from June). “What did you wish to discuss with me?”.

-/-

Bardel’s place- the old garage of some old car repair shop- is brimming with interesting magical and monster stuff. Jack pauses to poke what looks like a jar of eyeballs. “Cool”.

Bardel clears his throat pointedly, drawing the teen from his snooping. “You had something urgent to discuss?”. 

Jack blinks, his ‘problem’ momentarily forgotten. “Hmm? Oh yeah! This!”. He gives a big toothy smile and taps one of his newly pointed teeth. Bardel, is for once, bared of his neutral ignored expression. “Curious”. He approaches Jack and steers him to a seat on a table, then summons a ball of light to hover above them, illuminating the room. 

Jack let’s a ‘woah’ slip out of his mouth and it’s all he’s able to get out before his mouth is filled with an uncomfortable sensation. “‘Ey!”.

Bardel is leaned over him, examined his mouth, and he realizes that the uncomfortable sensation is magic, flowing around his teeth.

“Interesting. And when did this occur? From what I have seen humans do not typically have fangs”.

Jack pulls away from his prying eye and magic, and frowns, using his hand to wipe away the feel of magic in his mouth. “That’s why I came to you! This-“. He gestured to his mouth. “-started the other day. Out of nowhere! And I’m lowkey freaking out, and I really need some magic monster help please!”.

Bardel looks him over. “Nothing else seems to have changed. And if this is not a feature of human biology or adolescence, then what of your heritage?”.

Jack cocks his head to the side. “Uh... what?”.

Bardel rolls his eyes again. “Where do you come from? Who, or what, are your parents”.

Jack tenses and averts his gaze to the ground. “Oh um... y-yeah I don’t really know. I’m kind of an orphan”. He does weak jazz hands when he says it, as if it’s some sort of long-suffering joke he’s way too use to saying.

Which isn’t completely wrong. 

Bardel looks at him unimpressed. “So you have no ideas to what your heritage could be? I’ve never seen anything like this before. Perhaps you are simply some sort of half-breed”.

Jack scowled. “Half breed? Like what? Half human half monster? How would that even be possible?”.

“As I said, I haven’t seen anything like this before. And while monsters and humans exist in entirely separate realms, I suppose though I haven’t encounter it before it could be possible”. 

Jack groans. “So I could be half monster now? Oh that is great. So great. Just awsome. I’m not even good at being a human and now I’m part monster”.

“I can run some tests. I’m not entirely familiar with human biology, so I suggest you have your intellectual friend do the same. Return here tomorrow. I suppose I will try to see what I can find”.

Jack sighs. “Yeah okay. Thanks Bardel”. He stands, and sheepishly runs a hand through his hair. “Uh, do you mind not telling people about this yet?”. He holds his hands up quickly. “Not like I’m trying to hide it or anything I just wants be sure, I mean maybe it’s temporary. I just-“. 

“I’m not much for idle conversation”.

Jack breathes a sigh of relief. “Thank you!”. He tugs his bag off the ground, and lets out a sharp whistle, calling Rover to come pick him up. “I’ll be back tomorrow, same time!”.

-/- 

Jack feels lighter than he did last night, now that he’s got a plan. He tosses another street sign for Rover to fetch and snaps a picture of the monster-dog catching it in midair. 

Tugging out his journal he slips the photo in there and grins. He started it to keep him busy. Something to have when things were back to normal. 

He leans back onto the roof of the building he’s perched on and signs into the sky.

“I’m probably worrying over nothing”.

**Author's Note:**

> If u wanna eat a pie u gotta make it urself, so while I wrote this for me, y’all can have a slice too


End file.
